After formalizing transactions, production, investment process and another economic activities author has returned back to general dynamic in portfolio play. Idea of this article is to postulate the assumption on agent's strategy on money expenditure or other asset's strategy. There are two main assumptions. First one is that players exercise only transactions in environment with constant prices. Second assumption is that a force is introduced for specifying strategy. Forces influence the movement of portfolio according to classical Newton equation. Motivation is author's conviction about generality of some physic law. Only four expenditure strategies are studied. They are analogies to free fall, oscillator, more axis oscillator and general potential energy field. Author thinks that there is very reasonable economic interpretation of such artificial movements. Common approach in article is that the first equation is formalizing the exchange of goods and the second equation describes acceleration on player's current account using physical analogy. This type of acceleration of expenditure is then possible to formulate as integral of movements and is similar to conservation law for sum of kinetic and potential energy in physics. Article presents a vision of kinetic energy of money balances and potential energy of the stock of goods.
